Sony Ericsson K850, Troubleshooting Manual

Page: 20 / 101

K850
1203-2528 rev. 1
TROUBLESHOOTING System Connector Protection Test
TROU
B
L
E
S
H
O
OTIN
G
Current Consumption Test
Step 1:
Insert Local SIM Card and use the phone with the Normal SW (SSW) and dummy
battery connected to Power Supply Channel 1 VBATT according to Picture 1.
Instrument settings: Voltage: 3.8 Volt, Limiter 3A.
Measure the current when Phone is off. Check the current consumption at Power
Supply Channel 1 VBATT.
Picture 1
Current consumption in off mode should be less than 1mA.
If more than 1mA go to Dead Phone problems part 1 TRS guide.
Step 2:
Start the phone:
Measure the deep sleep current max 6mA typical between 0-3mA.
Make sure that the operator is running with deep sleep. (This operation can be
switched off by operator if the network is busy).
If phone using more than 6mA, then go to EMMA III and perform Software Update
Contents Refresh (SUCR).
Step 3 with Mobile Phone Tester Instrument
Insert Test SIM Card and use the phone with the Normal SW (SSW) and dummy
battery connected to Power Supply Channel 1 VBATT according to Picture 1.
Instrument settings: Voltage: 3.8 Volt, Limiter 3A.
Use Mobile Phone Tester Instrument in signalling mode direct connected to the
phone with RF Connector or use Shield Box if not possible. Phone Display must be
on during these tests to get correct current measurements.
Perform Radio TX measurements at GSM and WCDMA Band and compare with limits
according to text below.
System Connector Protection Test
Perform Diode and Ohm measurements with DMM
Connect the black probe at ground (Pin 9 system connector)
Pin at
X2400
Diode
Measurement
/ Volt
Ohm
Measurement
/ Ohm
SL 4 Action SL 5 Action
1 0L 0L N2402 if Not 0L C2422 if Not 0L
2 0.0 1.4 No Action L2405 If higher than 1.4 Ω
3 2.0 12K
N3101 if lower than 12K Ω
L2401 if higher than 12K Ω C2421 If lower than 12K Ω
4 1.0 1K
N3101 if lower than 1K Ω
L2402 if higher than 1K Ω C2420 if lower than 1K Ω
5 2.0 9K
N3101 if lower than 9K Ω
L2403 if higher than 9K Ω C2416 if lower than 9K Ω
6 2.0 9K
N3101 if lower than 9K Ω
L2404 if higher than 9K Ω C2415 if lower than 9K Ω
7 0L 0L Not connected Not connected
8 1.4 1.5K V2420 if lower than 1.5K Ω
R2451, R2440, R2436
if higher than 1.5K Ω
9 0 0 No Action
R2455 if Not 0 Ω between
X2400_Pin9 and PBA GND
10 0.7 200K-470K N2401if lower than 200K Ω
D2450 if lower than
200K Ω R2465 if higher
than 470K Ω
11 1.0 200K-470K N2401if lower than 200K Ω
D2450 if lower than
200K Ω R2466 if higher
than 470K Ω
12 0L 80K V2421 if lower than 80K Ω
C2423, C2424
if lower than 80K Ω
/ Current Comsumption Test
SEMC Troubleshooting Manual
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